Fatigue Crack Growth rate tests (FCGR)

Test samples smooth or with notch are pre-charged in gaseous hydrogen environment (T = RT ÷ 200 °C, p = 1 ÷ 200 bar) and then subjected to FCGR test according to conditions of interest, with reference to ASTM E 647. Diffusible hydrogen content is measured at the end of the test for each specimen to correlate mechanical performance and H content in the metal. Similarly, Jq and Kq tests can be carried out.